The American Funds Mortgage Fund - Class R2E (RMBEX) is a mutual fund that primarily invests in mortgage-backed securities issued or guaranteed by government agencies such as Fannie Mae and Freddie Mac. These securities are backed by a pool of mortgages, providing investors with a steady stream of income through interest payments. The fund may also invest in other fixed-income securities, such as corporate bonds and asset-backed securities. Class R2E shares are typically offered to retirement plans and other institutional investors, with a focus on long-term capital appreciation and income generation.